Drum type washing machine and method for assembling shaft system

ABSTRACT

A drum type washing machine reducing damage of a shaft system, and a method for assembling the shaft system are disclosed. The shaft system comprises a flange shaft coupled to a rear side of the drum to transmit the rotational force of the motor to the drum. A buffering material is provided between the drum and the flange shaft to distribute or absorb load or vibration transmitted from the drum to the flange shaft. The buffering material comprises a material having a liquid phase initially and changing to a solid phase having elasticity a predetermined period of time after contacting air. The buffering material is applied to a rear side of the drum or to a rear side of the shaft flange when assembling the shaft system.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit under 35 U.S.A. §119 of KoreanPatent Application No. 2005-0122761, filed on Dec. 13, 2005 in theKorean Intellectual Property Office, the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drum type washing machine, and, moreparticularly, to a drum type washing machine, which can reduce damage ofa shaft system serving to transmit rotational force of a motor to adrum, and a method for assembling the shaft system thereof.

2. Description of the Related Art

Generally, a washing machine is an apparatus which washes laundry usingelectric power. The washing machine can be generally classified into avertical type washing machine which has a rotating tub installedvertically in a body, and a drum type washing machine which has therotating tub installed horizontally therein. The drum type washingmachine comprises a drum positioned horizontally therein such that, asthe drum rotates alternately in the clockwise direction and thecounterclockwise direction, laundry can be washed while moving up anddown along with water in the inner portion of the rotating tub.

The drum type washing machine generally comprises a motor to supplypower to rotate the drum, and a shaft system to transmit rotationalforce of the motor to the drum. FIG. 1 is a perspective viewillustrating a drum, and a shaft system of a conventional drum typewashing machine. As shown in FIG. 1, a shaft system 1 of the drum typewashing machine comprises a flange shaft 3 installed at a rear side of adrum 2, and a drum rotating shaft 4 inserted into and integrally formedwith the center of the flange shaft 3. Here, the flange shaft 3comprises a plurality of wings 3 a, each of which extends radially fromthe center, and has a distal end fixed to the drum 2 by means of afastening member such as a bolt 5.

Accordingly, when the drum rotating shaft 4 is rotated by a motor (notshown), rotational force is transmitted to the flange shaft 3 integrallyformed with the drum rotating shaft 4, and is then delivered to the drum2 connected with the flange shaft 3 via the bolts 5, so that the drumrotating shaft 4, the flange shaft 3, and the drum 2 perform the samerotational movement.

However, since the flange shaft 3 is assembled at the distal end of eachwing 3 a to the drum only by the bolts 5 in the conventional washingmachine, there is a problem in that load of the laundry is concentratedon a specific portion of the shaft system of the washing machine insteadof being adequately distributed. Additionally, if the laundry is biasedto one side of the drum while the drum is rotated, a centrifugal forceis invoked by the rotating laundry, applying unequal load to the drum.The unequal load is transmitted to the shaft system 1 via fasteningportions of the bolts at the distal end of the flange shaft 3, andconcentrated on a portion where the flange shaft 3 is coupled to thedrum rotating shaft 4, so that the flange shaft 3 and the drum rotatingshaft 4 are damaged due to fatigue. Furthermore, since the shaft system1 of the conventional washing machine does not have a self-bufferingsystem to allow reduction of vibration by itself, the shaft system 1 isdamaged due to vibration and/or noise is generated therefrom. Suchproblem is especially evident when the drum rotates at high speedsand/or when the laundry load is heavy.

SUMMARY OF THE INVENTION

Accordingly, it is an aspect of the present invention to provide a drumtype washing machine, which can reduce damage of a shaft system causedby load applied thereto, and a method for assembling the shaft systemthereof.

It is another aspect of the present invention to provide the drum typewashing machine, which can reduce damage and noise of the shaft systemdue to vibration being generated upon rotation of a drum, and the methodfor assembling the shaft system thereof.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be apparentfrom the description, or may be learned by practice of the invention.

The foregoing and other aspects of the present invention are achieved byproviding a drum type washing machine, comprising a drum, a motor torotate the drum, and a flange shaft coupled to a rear side of the drumto transmit rotational force of the motor to the drum, wherein abuffering material is provided between the drum and the flange shaft todistribute or absorb load or vibration transmitted from the drum to theflange shaft.

The buffering material may fill up a gap formed between the drum and theflange shaft to bond the drum and the flange shaft.

The buffering material may comprise a material having a liquid phaseinitially and changing to a solid phase having elasticity apredetermined period of time after contacting air. The bufferingmaterial may comprise a silicon material.

The flange shaft may be formed with a recess to be filled with thebuffering material.

In accordance with another aspect of the present invention, there isprovided a method for assembling a shaft system of a drum type washingmachine in which the shaft system comprises a flange shaft installed ata rear side of a drum to transmit rotational force of a motor to thedrum, and a drum rotating shaft, the method comprising: applying abuffering material to a portion at the rear side of the drumcorresponding to an installation position of the flange shaft; andinstalling the flange shaft to the drum having the buffering materialapplied thereto.

In accordance with yet another aspect of the present invention, there isprovided a method for assembling a shaft system of a drum type washingmachine in which the shaft system comprises a flange shaft installed ata rear side of a drum to transmit rotational force of a motor to thedrum, and a drum rotating shaft, the method comprising: applying abuffering material to a surface of the flange shaft brought into contactwith the drum; and installing the flange shaft having the bufferingmaterial to the drum.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe embodiments, taken in conjunction with the accompanying drawings, ofwhich:

FIG. 1 is a perspective view illustrating a drum, and a shaft system ofa conventional drum type washing machine;

FIG. 2 is a perspective view illustrating an appearance of a drum typewashing machine in accordance with the present invention;

FIG. 3 is a side sectional view illustrating the construction of thedrum type washing machine;

FIG. 4 is an enlarged view of Part A of FIG. 3 for illustrating a gapbetween a drum and a flange shaft excluding a buffering material; and

FIGS. 5 and 6 are perspective views illustrating a shaft systemassembled to the drum of the washing machine in accordance with thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings. The embodiments are described below to explain the presentinvention by referring to the figures.

FIG. 2 is a perspective view illustrating an appearance of a drum typewashing machine in accordance with the present invention, and FIG. 3 isa side sectional view illustrating the construction of the drum typewashing machine.

Referring to FIGS. 2 and 3, a drum type washing machine according to thepresent invention comprises a housing 10 defining an outer appearance ofthe washing machine, a water tub 11 installed in the housing 10 tocontain water for washing laundry, and a drum 12 rotatably installed inthe water tub 11 to receive the laundry which will be washed byoperation of the washing machine therein. The housing 10 has a door 13attached to a front side thereof to open or close an opening throughwhich the laundry is accessed, and a control panel 14 provided at thefront side to control the operation of the washing machine.

The housing 10 is provided at an upper portion therein with a watersupply pipe 15 and a detergent supply device 16 to supply water anddetergent to the tub 11, respectively, and provided at a lower portiontherein with a water discharge pump 17 and a water discharge pipe 18 todischarge water from the tub 11 to an outside of the housing 10.

The housing 10 is further provided with a motor 20 at an outside of thetub 11 to rotate the drum 12 in the clockwise direction or thecounterclockwise direction, and a shaft system 30 at an outside of arear side 12 a of the drum 12. The shaft system 30 comprises a flangeshaft 31, and a drum rotating shaft 32 to transmit rotational force ofthe motor 20 to the drum 12. The drum rotating shaft 32 is coupled tothe center of the flange shaft 31, and extends outwardly from the tub 11so as to engage with the motor 20. The flange shaft 31 has a pluralityof wings 33, each of which extends radially from the center of theflange shaft 31 coupled to the drum rotating shaft 32, and has a distalend fixed to the drum 12 by means of a fastening member such as a bolt34.

A cylindrical bearing housing 21 is provided at the rear side of the tub11, and has bearings 22 on the drum rotating shaft 32 such that the drumrotating shaft 32 can be rotatably supported thereby.

Accordingly, as the drum rotating shaft 32 is rotated by the motor 20,the flange shaft 31 coupled to the drum rotating shaft 32 is alsorotated, so that the drum 12 coupled to the flange shaft 31 is rotated,causing the laundry to be washed or extracted of water therein. In themeantime, if unequal load is applied because the laundry is biased toone side of the drum 12 during rotation of the drum 12, or if vibrationis generated due to high speed rotation of the drum 12, the load andvibration are transmitted to the shaft system 30, and accumulate fatigueon the flange shaft 31 and the drum rotating shaft 32.

In this regard, the drum type washing machine of the present inventioncomprises a buffering material 40 between the drum and the flange shaft31 to distribute or absorb the load or the vibration transmitted fromthe drum 12 to the flange shaft 31.

FIG. 4 is an enlarged view of Part A of FIG. 3 for illustrating a gapbetween a drum and a flange shaft excluding a buffering material, andFIGS. 5 and 6 are perspective views illustrating a shaft systemassembled to the drum of the washing machine in accordance with thepresent invention.

As shown in FIGS. 3 and 4, a buffering material 40 serves to allow thedrum 12 and the flange shaft 31 to be bonded to each other over a widecontact area by filling up a gap G created between the drum 12 and theflange shaft 31 when assembling the shaft system 30. Then, when load istransmitted from the drum 12 to the shaft system 30, the load istransmitted in a distributed state over the wide contact area via thebuffering material 40 rather than in a concentrated state on a boltfastening portion 35 of the flange shaft 31, thereby reducing stressapplied to the flange shaft 31 due to the load. In addition, whenvibration is transmitted to the shaft system 30 due to the rotation ofthe drum 12, the buffering material 40 absorbs the vibration between thedrum 12 and the shaft system 30, thereby reducing damage or noise of theshaft system due to the vibration. Although preferably, the entire gapportion is filled with the buffering material, certain portions may beleft empty.

In consideration of the structural characteristics or the weight of theflange shaft 31, a recess 36 is formed on the flange shaft 31, andfilled with the buffering material 40 such that the flange shaft 31 andthe drum 12 are bonded to each other over the wide contact area via thebuffering material 40.

In order to allow the buffering material 40 to effectively fill up thegap G between the drum 12 and the flange shaft 31 while allowing thebuffering material 40 to effectively reduce the vibration transmittedfrom the drum 12 therethrough, the buffering material 40 is preferablycomposed of a material, which has a liquid phase initially, i.e., beforebeing applied to the recess 36, and changes to a solid phase with apredetermined elasticity in a state of contacting air. For example, sucha material includes silicon materials such as a silicon bond, a siliconrubber, and the like. However, the buffering material 40 is not limitedto the silicon materials, but any other types of material having theproperties as described above may be used for the buffering material 40.

As shown in FIGS. 3 and 5, when assembling the shaft system 30 to thedrum 12, the buffering material 40 is applied to a portion at the rearside 12 a of the drum 12 corresponding to an installation position ofthe flange shaft 31. Then, the flange shaft 31 is mounted to the drum 12having the buffering material 40 applied thereto such that the bufferingmaterial 40 fills up the gap between the drum 12 and the flange shaft31.

Alternatively, as shown in FIGS. 3 and 6, it is possible to assemble theshaft system 30 to the drum 12 in such a manner that, after applying thebuffering material 40 to a rear surface 31 a of the flange shaft 31,that is, a surface of the flange shaft 31 which will be brought intocontact with the drum 12, the flange shaft 31 having the bufferingmaterial 40 applied thereto is mounted to the drum 12.

As apparent from the above description, the present invention has anadvantageous effect in that, when the buffering material applied to thedrum or the flange shaft of the shaft system, it causes the load to bedistributed and absorbs the vibration transmitted from the drum to theshaft system upon rotation of the drum, thereby reducing damage or noiseof the shaft system.

Although a few embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatvarious modifications, additions and substitutions may be made in theseembodiments without departing from the principle and spirit of theinvention, the scope of which is defined in the claims and theirequivalents.

1. A drum type washing machine comprising: a drum, a motor to rotate thedrum, and a flange shaft coupled to a rear side of the drum to transmitrotational force of the motor to the drum, wherein a buffering materialis provided between the drum and the flange shaft to distribute orabsorb load or vibration transmitted from the drum to the flange shaft.2. The washing machine according to claim 1, wherein the bufferingmaterial fills up a gap formed between the drum and the flange shaft tobond the drum and the flange shaft.
 3. The washing machine according toclaim 2, wherein the buffering material comprises a material having aliquid phase initially and changing to a solid phase having elasticity apredetermined period of time after contacting air.
 4. The washingmachine according to claim 3, wherein the buffering material comprises asilicon material.
 5. The washing machine according to claim 2, whereinthe flange shaft is formed with a recess to be filled with the bufferingmaterial.
 6. A method for assembling a shaft system of a drum typewashing machine, the shaft system comprising a flange shaft installed ata rear side of a drum to transmit rotational force of a motor to thedrum, and a drum rotating shaft, the method comprising: applying abuffering material to a portion at the rear side of the drumcorresponding to an installation position of the flange shaft; andinstalling the flange shaft to the drum having the buffering materialapplied thereto.
 7. The method according to claim 6, wherein thebuffering material comprises a material having a liquid phase initiallyand changing to a solid phase having elasticity a predetermined periodof time after contacting air.
 8. The method according to claim 7,wherein the buffering material comprises a silicon material.
 9. A methodfor assembling a shaft system of a drum type washing machine, the shaftsystem comprising a flange shaft installed at a rear side of a drum totransmit rotational force of a motor to the drum, and a drum rotatingshaft, the method comprising: applying a buffering material to a surfaceof the flange shaft brought into contact with the drum; and installingthe flange shaft having the buffering material to the drum.
 10. Awashing machine comprising: a container for holding a load of clothesfor washing; a motor providing a rotational driving force; and a flangeshaft coupled to said motor and said container for transmitting therotational driving force of said motor to said container; wherein abuffering material is provided between said container and said flangeshaft.
 11. The washing machine as claimed in claim 10 further comprisinga shaft for coupling said motor to said flange shaft.
 12. The washingmachine as claimed in claim 11 wherein said washing machine is a drumtype.
 13. The washing machine as claimed in claim 12 wherein said flangeshaft has a plurality of arms extending outwardly from a center portionof said flange shaft.
 14. The washing machine as claimed in claim 13wherein said buffering material is provided between said container andat least one of said extending arms.
 15. The washing machine as claimedin claim 14 wherein said buffering material fills up a gap formedbetween said container and said flange shaft.
 16. The washing machine asclaimed in claim 15 wherein said buffering material bonds said containerand said flange shaft.
 17. The washing machine as claimed in claim 16wherein said buffering material has a substantial elasticity forabsorbing shock.
 18. The washing machine as claimed in claim 17 whereinsaid buffering material comprises of a material having a liquid phaseinitially and changing to a solid phase a predetermined period of timeafter contacting air.
 19. The washing machine as claimed in claim 18wherein said buffering material comprises of silicon material.
 20. Thewashing machine as claimed in claim 19 wherein said flange is formedwith a recess to be filled with said buffering material.
 21. The washingmachine as claim in claim 10 wherein said flange shaft has a recess forreceiving said buffering material.
 22. The washing machine as claimed inclaim 11 wherein said buffering material is a silicon material.
 23. Thewashing machine as claimed in claim 10 wherein said washing machine is adrum type and said container is a drum.
 24. The washing machine asclaimed in claim 23 wherein said buffering material has a substantialelasticity for absorbing vibration generated by said drum.
 25. Thewashing machine as claimed in claim 23 wherein said buffering materialprovides distribution of load to various portions of the flange shaft.26. The washing machine as claimed in claim 10 wherein said flange shafthas a plurality of arms extending away from a center portion of saidflange shaft.
 27. The washing machine as claimed in claim 26 whereinsaid flange shaft has a fastener on said arms for fixing said flangeshaft to said container.
 28. The washing machine as claimed in claim 10further comprising a water closet, wherein said container is disposedwithin said water closet.
 29. The washing machine as claimed in claim 28wherein said container has a plurality of perforations for allowingwater to be moved between said container and said water closet.
 30. Thewashing machine as claimed in claim 29 wherein said flange shaft isdirectly coupled to said container so as to rotate in unison.